3D PrintingSUBMITTED BY:-ARJUN MAHESHWARI 1214331038EC:-2 (3rd year)Introduction3D printing is a form of additive manufacturing technology where a three dimensional object is created by laying down successive layers of material.

3D printing is achieved using an additive process, where successive layers of material are laid down in different shapes.HistoryThe technology for printing physical 3D objects from digital data was first developed by Charles Hull in 1984. He named the technique as Stereo lithography and obtained a patent for the technique in 1986.In 1993, Massachusetts Institute of Technology (MIT) patented another technology, named "3 Dimensional Printing techniques", which is similar to the inkjet technology used in 2D Printers.In 2005, Z Corp. launched a breakthrough product, named Spectrum Z510, which was the first high definition color 3D Printer in the market.

TerminologyAdditive manufacturing - refers to technologies that create objects through sequential layering.

Rapid prototyping - is a group of techniques used to quickly fabricate a scale model of a physical part or assembly using three-dimensional computer aided design (CAD) data.

Subtractive processes - removal of material by methods such as cutting or drilling.

Stereo lithography was defined by Charles W. Hull as a "system for generating three-dimensional objects by creating a cross-sectional pattern of the object to be formed"

3D Printable Models3D printable models may be created with a computer aided design package or via 3D scanner.

The manual modeling process of preparing geometric data for 3D computer graphics is similar to plastic arts such as sculpting.

3D scanning is a process of analyzing and collecting data of real object; its shape and appearance and builds digital, three dimensional models.

Rapid Prototyping SlicingPrintingTo perform a print, the machine reads the design from 3D printable file (STL file).STL file STereoLithographyIt lays down successive layers of liquid, powder, paper or sheet material to build the model from a series of cross sections.These layers, which correspond to the virtual cross sections from the CAD model, are joined or automatically fused to create the final shape.Printer resolution describes layer thickness and X-Y resolution in dpi (dots per inch), or micrometers.X-Y resolution is comparable to that of laser printers. The particles (3D dots) are around 50 to 100 m (510 to 250 DPI) in diameter.

FinishingThough the printer-produced resolution is sufficient for many applications, printing a slightly oversized version of the desired object in standard resolution and then removing material with a higher-resolution subtractive process can achieve greater precision.

Supports are removable or dissolvable upon completion of the print, and are used to support overhanging features during construction.Additive ProcessesExtrusion deposition (Fused deposition modeling)Granular materials bindingLaminationPhoto polymerizationExtrusion deposition (Fused Deposition Modeling)

Fused deposition modeling (FDM) is an additive manufacturing technology commonly used for modeling, prototyping, and production applications.FDM works on an "additive" principle by laying down material in layers; a plastic filament or metal wire is unwound from a coil and supplies material to produce a part.Various polymers are usedAcrylonitrile Butadiene Styrene (ABS)Polycarbonate (PC), Polylactic Acid (PLA)High Density Polyethylene (HDPE)PC/ABSPolyphenylsulfone (PPSU).

1 nozzle ejecting molten plastic2 deposited material (modeled part)3 controlled movable tableGranular Materials BindingThe technique fuses parts of the layer, and then moves the working area downwards, adding another layer of granules and repeating the process until the piece has built up.

This process uses the unfused media to support overhangs and thin walls in the part being produced.

A laser is typically used to sinter the media into a solid.

LaminationSheet is adhered to a substrate with a heated roller.Laser traces desired dimensions of prototype.Laser cross hatches non-part area to facilitate waste removal.Platform with completed layer moves down out of the way.Fresh sheet of material is rolled into position.Platform moves up into position to receive next layer.The process is repeated.

1. Foil supply

2. Heated roller

3. Laser beam

4. Scanning prism

5. Laser unit

6. Layers

7. Moving platform

8. WastePhotopolymerizationPhotopolymerization is primarily used in stereolithography (SLA) to produce a solid part from a liquid.In Digital Light Processing (DLP), a vat of liquid polymer is exposed to light from a DLP projector under safelight conditions. The exposed liquid polymer hardens.The build plate then moves down in small increments and the liquid polymer is again exposed to light. The process repeats until the model has been built. Inkjet printer systems like the Objet PolyJet system spray photopolymer materials onto a build tray in ultra-thin layers (between 16 and 30 m) until the part is completed.

Stereolithography Apparatus

Printers

RepRap version 2.0 (Mendel) MakerBot Cupcake CNC. Airwolf 3D AW3D v.4 (Prusa)ApplicationsIndustrial usesRapid PrototypingRapid ManufacturingMass CustomizationMass ProductionDomestic and hobbyist usesClothing3D Bio-printing3D Printing For Implant And Medical Device3D Printing Services

FutureFuture applications for 3D printing might include creating open-source scientific equipment to create open source labs.Science-based applications like reconstructing fossils in paleontology.Replicating ancient and priceless artifacts in archaeology.Reconstructing bones and body parts in forensic pathology.Reconstructing heavily damaged evidence acquired from crime scene investigations.The technology currently being researched for building construction.Effects of 3D printingSpace explorationMaking spare parts on the flyCheaper and more efficient space exploration Social changeConventional relationship between the home and the workplace might get further eroded. It becomes easier to transmit designs for new objects around the globe.

ChallengesNearly anything can be printed by 3D printers and this is troubling prospect if criminals use 3D printers to create illegal products.

Firearms could be downloaded and reproduced by anybody with a 3D printer.

Conclusion3D Printing technology could revolutionize and re-shape the world. Advances in 3D printing technology can significantly change and improve the way we manufacture products and produce goods worldwide.

If the last industrial revolution brought us mass production and the advent of economies of scale - the digital 3D printing revolution could bring mass manufacturing back a full circle - to an era of mass personalization, and a return to individual craftsmanship.

Referenceshttp://mashable.com/2014/03/06/3d-printed-blood-vessels/https://www.rtejournal.de/ausgabe10/3562http://en.wikipedia.org/wiki/3D_printinghttp://www.3dprinter.net/reference/what-is-3d-printing

Thank You